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Re: inline-limit: some experimental feedback

Gerald Pfeifer <> writes:

> On Tue, 21 Aug 2001, Daniel Berlin wrote:
> > Errr, they are due to not inlining iterators, because we hit the
>> inlining limit.
>> I've verified this through profiling his applications.
>> What happens is we don't inline things where the call cost is less
>> than the cost to just inline, which happens quite often with
>> iterators, because we've already hit the various inlining limits.
> Bad, but something like that had to be the cause, else I wouldn't
> have suffered from such an incredible slow-down.
>> This is the main missing heuristic.
> Would this be hard to implement? Actually, didn't you have a patch
> addressing this?
>> Without it, you need to crank up the inline limit enough to get all
>> the functions where call cost exceeds inline cost to be inlined.
>> When you do that, you generate enough excess code to slow down
>> compilation by a large amount.
> Though, even if I set the limit to 10000, the generated code is still
> measurably slower than for GCC 2.95.x.

Code bloat isn't good for cache behavior, etc, either.

> Again, I'm willing to hand out our sources including a benchmark suite
> who's interested to work on this, and I can also try patches and perform
> such benchmarks by myself.
> Gerald
> -- 
> Gerald "Jerry"

"All the plants in my house are dead -- I shot them last night.
I was torturing them by watering them with ice cubes.
"-Steven Wright

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